A flow splitter including a first plate being immobile and a second plate being turnable with respect to the first plate. The first plate includes a central part, and the central part includes a slot and two side parts disposed at two ends of the slot, respectively. The second plate includes a first subplate and a second subplate, and the first subplate includes one end provided with a flange. The second plate is coupled to the first plate. The first subplate and the second subplate are disposed at two side of the slot; two sides of the second plate include two gaps, respectively. The two side parts of the first plate are disposed in the two yaps, respectively.